The health check thresholds for monitoring of free space on the filesystem that contains the Cloudera Manager Agent's
log directory. Specified as a percentage of the capacity on that filesystem. This setting is not used if a Cloudera Manager Agent Log Directory Free Space Monitoring Absolute Thresholds setting is
configured.

The health check thresholds for monitoring of free space on the filesystem that contains the Cloudera Manager Agent's
parcel directory. Specified as a percentage of the capacity on that filesystem. This setting is not used if a Cloudera Manager Agent Parcel Directory Free Space Monitoring Absolute Thresholds setting
is configured.

The health check thresholds for monitoring of free space on the filesystem that contains the Cloudera Manager Agent's
process directory. Specified as a percentage of the capacity on that filesystem. This setting is not used if a Cloudera Manager Agent Process Directory Free Space Monitoring Absolute Thresholds
setting is configured.

host_agent_process_directory_free_space_percentage_thresholds

critical:never, warning:never

PERCENT

Host Agent Status

This is a host health test that checks that the host's Cloudera Manager Agent is heartbeating correctly to the Cloudera Manager Server, is in contact with the Host Monitor, and has the
correct software version. A failure of this health test may indicate a lack of connectivity between the host's Cloudera Manager Agent and the Cloudera Manager Server, a lack of connectivity betwen
the host's Cloudera Manager Agent and the Host Monitor, or that the Cloudera Manager Agent or Host Monitor software is out of date. Check the status of the Cloudera Manager Agent by running
/etc/init.d/cloudera-scm-agent status on the host, or look in the host's Cloudera Manager Agent logs for more details. If this test reports a software version mismatch
between the Cloudera Manager Agent and the Host Monitor, check the version of each component by consulting the appropriate logs or the appropriate status web pages. This test can be enabled or
disabled using the Host Process Health Test host configuration setting.

Short Name: Agent Status

Property Name

Description

Template Name

Default Value

Unit

Host Process Health Test

Enables the health test that the host's process state is consistent with the role configuration

host_scm_health_enabled

true

no unit

Host Clock Offset

This is a host health test that checks if the host's system clock appears to be out-of-sync with its NTP server(s). The test uses the 'ntpdc -np' command to check that the host is
synchronized to an NTP peer and that the absolute value of the host's clock offset from that peer is not too large. If the command fails, NTP is not synchronized to a server, or the host's NTP daemon
is not running or cannot be contacted, the test will return "Bad" health. The 'ntpdc -np' output contains a row for each of the host's NTP servers. The row starting with a '*' contains the peer to
which the host is currently synchronized. No row starting with a '*' indicates that the host is not currently synchronized. Communication errors and too large an offset between the peer and the host
time are examples of conditions that can lead to a host being unsynchronized. Make sure that UDP port 123 is open in any firewall that is in use. Check the system log for ntpd messages related to
configuration errors. Use 'ntpdc -c iostat' to verify that packets are sent and recieved between the different peers. More information about the conditions of each peer can be found by running the
command 'ntpq -c as'. The output of this command includes the association ID that can be used in combination with 'ntpq -c "rv <association id>"' to get more information about the status of
each such peer. The command 'ntpq -c pe' can also be used to return a summary of all peers and the reason why they are not in use. If NTP is not in use on the host, this check should be disabled for
the host using the configuration options shown below. Cloudera recommends using NTP for time synchronization of Hadoop clusters. A failure of this health test can indicate a problem with the host's
NTP service or configuration. This test can be configured using the Host Clock Offset Thresholds host configuration setting.

Short Name: Clock Offset

Property Name

Description

Template Name

Default Value

Unit

Host Clock Offset Thresholds

The thresholds for the host clock offset health test. The test compares this threshold against the absolute value of
the clock offset reported by the host's NTP service from the 'ntpdc -np' command. Setting both the warning and critical threshold values to never turns off collection of the clock offset by the
Cloudera Manager Agent. If NTP is not in use, both threshold values should be set to never. Cloudera recommends using NTP for time synchronization of Hadoop clusters.

host_clock_offset_thresholds

critical:10000.0, warning:3000.0

MILLISECONDS

Host DNS Resolution

This is a host health test that checks that the host's hostname and canonical name are consistent when checked from a Java process, and that the DNS resolution completes in a timely
manner. The DNS resolution duration is calculated by measuring the time taken to call getLocalHost in a Java process on this host. Note that DNS information may be cached on the host, and this
caching can affect the reported resolution duration. A failure of this health test may indicate that the host's DNS configuration is not correct or the host's DNS server is responding slowly. Check
the Cloudera Manager Agent log for the names that were detected by this test or for errors running the Java process. The hostname and canonical name are considered to be consistent if the hostname or
the hostname plus a domain name is the same as the canonical name. This health test uses domain names from the domain and search lines in /etc/resolv.conf. This health test does not consult
/etc/nsswitch.conf and may give incorrect results if /etc/resolv.conf is not used by the host. There may be a delay of up to 5 minutes before this health test picks up changes to /etc/resolv.conf.
This test can be configured using the Hostname and Canonical Name Health Check host configuration setting.

Short Name: DNS Resolution

Property Name

Description

Template Name

Default Value

Unit

Hostname and Canonical Name Health Check

Whether the hostname and canonical names for this host are consistent when checked from a Java process.

host_dns_resolution_enabled

true

no unit

Host Frame Errors

This is a host health test that checks for network frame errors across all network interfaces. A failure of this health test may indicate a problem with network hardware (e.g. switches)
and can potentially cause other service or role-level performance problems. Check the host and network hardware logs for more details. This test can be configured using the Host
Network Frame Error Percentage Thresholds, Host Network Frame Error Check Window, Host Network Frame Error Test Minimum Required
Packets host configuration settings.

Short Name: Frame Errors

Property Name

Description

Template Name

Default Value

Unit

Host Network Frame Error Check Window

The amount of time over which the host frame error checks for frame errors.

host_network_frame_errors_window

15

MINUTES

Host Network Frame Error Percentage Thresholds

The health check thresholds for the percentage of received packets that are frame errors.

host_network_frame_errors_thresholds

critical:0.5, warning:any

PERCENT

Host Network Frame Error Test Minimum Required Packets

The minimum number of received packets that must be received within the test window for this test to return "Bad"
health. If less that this number of packets is received during the test window, the health check will never return "Bad" health.

host_network_frame_errors_floor

0

no unit

Host Network Interface Speed

This is a host health test that checks for network interfaces that appear to be operating at less than full speed. The Cloudera Manager Agent uses ethtool ioctl to determine the network
interface speed and duplex mode. A failure of this health test may indicate that network interface(s) may be configured incorrectly and may be causing performance problems. Use the ethtool command to
check and configure the host's network interfaces to use the fastest available link speed and duplex mode. For inactive interfaces or for interfaces that do not support ethtool ioctl, the Cloudera
Manager Agent cannot collect speed metrics. If the Cloudera Manager Agent fails to collect speed metrics for all network interfaces on the host, the test is disabled. This test can be configured
using the Host's Network Interfaces Slow Link Modes Thresholds, Network Interface Expected Link Speed and Network
Interface Expected Duplex Mode host configuration settings.

Short Name: Network Interface Speed

Property Name

Description

Template Name

Default Value

Unit

Host's Network Interfaces Slow Link Modes Thresholds

The thresholds for the health check of the number of network interfaces that appear to be operating at less than full
speed.

host_network_interfaces_slow_mode_thresholds

critical:never, warning:any

no unit

Network Interface Expected Duplex Mode

The expected duplex mode for network interfaces.

host_nic_expected_duplex_mode

Full

no unit

Network Interface Expected Link Speed

The expected network interface link speed.

host_nic_expected_speed

1000

no unit

Host Swapping

This is a health test that checks that the host has not swapped out more than a certain number of pages over the last fifteen minutes. A failure of this health test may indicate
misconfiguration of the host operating system, or too many processes running on the host. Try reducing vm.swappiness, or add more memory to the host. This test can be
configured using the Host Memory Swapping Thresholds, Host Memory Swapping Check Window host configuration settings.

Short Name: Swapping

Property Name

Description

Template Name

Default Value

Unit

Host Memory Swapping Check Window

The amount of time over which the memory swapping test checks for pages swapped.

host_memswap_window

15

MINUTES

Host Memory Swapping Thresholds

The health check thresholds of the number of pages swapped out on the host in the last 15 minutes

If this documentation includes code, including but not limited to, code examples, Cloudera makes this available to you under the terms of the Apache License, Version 2.0, including any required
notices. A copy of the Apache License Version 2.0 can be found here.